Interesting observation when decelerating.

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mdracer76

mdracer76

Joined
Apr 28, 2013
Messages
53
Location
NoVA
Its been 2 months, and 2000 miles for me, and my 2013 Panigale S.

After 600 Miles, I had the break in service performed, and the Termignoni Slip Ons installed by my Dealer. (up map also installed by dealer)

I've noticed, on occasion, some flames / popping on decel, and sometimes between shifts. It sounds awesome, and according to some buddies riding behind me, I'm shooting some nice blue flames.

Here is my strange observation. If I am 100% off the throttle, and got the rpms up high, and decelerating, no brakes, DQS is on, and try to upshift (without clutch) while its decelerating, it wont do into the next gear, but will make the bike backfire / shoot flames. It will shoot a flame every time I try to upshift without the clutch, using DQS. if I try 3 or 4 times while its higher in the RPMS, then I get 3 - 4 'pops'.

Everything on the bike seems to be running in top order. it pulls like crazy in every gear, so mechanically, I think its OK.

Can someone else try this, and see if they observe the same thing?

Thanks!
 
mdracer76 said:
Its been 2 months, and 2000 miles for me, and my 2013 Panigale S.

After 600 Miles, I had the break in service performed, and the Termignoni Slip Ons installed by my Dealer. (up map also installed by dealer)

I've noticed, on occasion, some flames / popping on decel, and sometimes between shifts. It sounds awesome, and according to some buddies riding behind me, I'm shooting some nice blue flames.

Here is my strange observation. If I am 100% off the throttle, and got the rpms up high, and decelerating, no brakes, DQS is on, and try to upshift (without clutch) while its decelerating, it wont do into the next gear, but will make the bike backfire / shoot flames. It will shoot a flame every time I try to upshift without the clutch, using DQS. if I try 3 or 4 times while its higher in the RPMS, then I get 3 - 4 'pops'.

Everything on the bike seems to be running in top order. it pulls like crazy in every gear, so mechanically, I think its OK.

Can someone else try this, and see if they observe the same thing?

Thanks!
Click to expand...


Yup all Normal...does the same...with the DQS in ON position, bike will only clearly enter into gear while your "ACCELERATING" not decellerating....

Not an issue!
 
I love my "popping" sound when upshifting. All my QS-equipped bikes have done it as the momentary ignition cut caused by the shift-rod sensor allows unburnt fuel to be sucked out the exhaust valve into the exhaust system. This unburnt gas is still traveling down the headers/exhaust when it hits the super-hot piping, causing the "pop" which becomes a "bang" at WFO shifts.

My 2012 Pani with Termi slips and up map does it like clockwork when I shift between 3500-5000 rpm in almost every gear. I haven't been to the track yet so I'm not sure what happens when I shift through 4-5 gears at 10,500-11,500.

What you describe on decel, with popping, I do not experience. Usually popping on decel is the sign of lean mapping in the off-throttle position. I've had other bikes do it and usually I dial it out with a fuel controller but never had this happen on the Pani yet.
 
The quick shifter is chopping fuel as it would if you were on the throttle, causing a lean spot and the backfire you're hearing. However, the transmission is already loaded in the direction of deceleration so chopping fuel doesn't unload it (as it does if you're accelerating) and you can't shift.

In other words, what you're experiencing is normal. If you want to downshift from off throttle or neutal throttle use the clutch.
 
Cloner said:
The quick shifter is chopping fuel as it would if you were on the throttle, causing a lean spot and the backfire you're hearing. However, the transmission is already loaded in the direction of deceleration so chopping fuel doesn't unload it (as it does if you're accelerating) and you can't shift.

In other words, what you're experiencing is normal. If you want to downshift from off throttle or neutal throttle use the clutch.
Click to expand...


"exactamente" +1
 
Cloner said:
The quick shifter is chopping fuel as it would if you were on the throttle, causing a lean spot and the backfire you're hearing. However, the transmission is already loaded in the direction of deceleration so chopping fuel doesn't unload it (as it does if you're accelerating) and you can't shift.

In other words, what you're experiencing is normal. If you want to downshift from off throttle or neutal throttle use the clutch.
Click to expand...


+2
 
Cloner said:
The quick shifter is chopping fuel as it would if you were on the throttle, causing a lean spot and the backfire you're hearing. However, the transmission is already loaded in the direction of deceleration so chopping fuel doesn't unload it (as it does if you're accelerating) and you can't shift.

In other words, what you're experiencing is normal. If you want to downshift from off throttle or neutal throttle use the clutch.
Click to expand...

-1

The DQS does not cut fuel and cause a lean spot. Like JeffD said, it cuts ignition and leaves unburnt fuel to pop in the hot exhaust pipes, not a backfire. A backfire is when combustion takes place in the intake manifold, common with carburated engines. I haven't seen or heard a backfire since the 1980's.

This is where your exhaust flames come from, combustion in the header. A backfire would set your air filter on fire, lol.

This is totally normal and the same thing will even happen on the rev limiter, or if you use a two-step or any other spark retarding rev limiter.

The reason you want to stay on the gas is because when it is done limiting, in this case when the shift is complete, you want fuel ready to go so the shift is smooth, otherwise it will clunk as you roll back on the throttle.
 
Thank you for your correction, Higgs. Ya learn something new every day. Chopping fuel could cause a lean pop (that's what happens with most aftermarket systems like Bazzaz) while chopping spark leaves unburned hydrocarbons to burn inside the exhaust system.

However, your distinction of backfires occuring only through the intake system incorrect. The term is used to describe any untimely detonation of fuel in an internal combustion engine. Back-fire - Wikipedia, the free encyclopedia
 
Cloner said:
Thank you for your correction, Higgs. Ya learn something new every day. Chopping fuel could cause a lean pop (that's what happens with most aftermarket systems like Bazzaz) while chopping spark leaves unburned hydrocarbons to burn inside the exhaust system.

However, your distinction of backfires occuring only through the intake system incorrect. The term is used to describe any untimely detonation of fuel in an internal combustion engine. Back-fire - Wikipedia, the free encyclopedia
Click to expand...

fair enough. in this neck of the woods it always meant backwards fire, exhaust being at least the correct direction....

wiki says: The term derives from parallel experiences with early unreliable firearms or ammunition, in which the explosive force was directed out at the breech instead of the muzzle

however it also says the term's meaning has expanded....heres to living in the stone age.
 
mig1199 said:
Yup all Normal...does the same...with the DQS in ON position, bike will only clearly enter into gear while your "ACCELERATING" not decellerating....

Not an issue!
Click to expand...

Correct, I realize this. What I am curious about is if other owners experience the same 'popping' on deceleration while attempting to upshift with DQS enabled.
 
Cloner said:
The quick shifter is chopping fuel as it would if you were on the throttle, causing a lean spot and the backfire you're hearing. However, the transmission is already loaded in the direction of deceleration so chopping fuel doesn't unload it (as it does if you're accelerating) and you can't shift.

In other words, what you're experiencing is normal. If you want to downshift from off throttle or neutral throttle use the clutch.
Click to expand...

Agreed, and using the clutch works perfectly in this scenario. What I am describing is an effort to replicate the issue by NOT using the clutch. :)
 
Cloner said:
The quick shifter is chopping fuel as it would if you were on the throttle, causing a lean spot and the backfire you're hearing. However, the transmission is already loaded in the direction of deceleration so chopping fuel doesn't unload it (as it does if you're accelerating) and you can't shift.

In other words, what you're experiencing is normal. If you want to downshift from off throttle or neutal throttle use the clutch.
Click to expand...

You are correct: being off the gas and tripping the quickshifter won't unload the trans allowing a shift, since it's not the engine loading the trans but the rear wheel.

However, you don't HAVE to use the clutch when downshifting; you can use the same concept of unloading the trans to downshift as well, but you have to do it manually. If you are on the gas at all, the second you let go of the throttle to let it spring back to the stop, you can drop a gear and it will drop just as smoothly as the QS upshifts, if not smoother. You can do it again if you come back on the gas the slightest amount (just enough to load the trans from the engine) and drop it again, while clicking the shifter down again at the exact same time. I do this all the time, it's so smooth you almost couldn't tell if it weren't for the sound of the engine rev level.

A lot of people freak out when someone talks about clutchless downshifting because they simply don't understand the concepts of what is going on in the engine/trans/drivetrain. The reality is, it's the exact same thing: a specific unloading/loading of the trans, and shifting. Just in different directions.

Edit: I'm not speaking directly at you Cloner, when it comes to not understanding. I'm just saying a lot of the forum biking community in general seems to have a hard time grasping some of these concepts.
 
MacaveliMC said:
Sorry remind me what AIS is again?

And I thought the bike came stock with a "race"ish filter?
Click to expand...

air injection which is commonly referred to as PAIR on motorcycles. injects clean air into exhaust to help burn off additional emissions. skews AFR readings so some people delete the system before getting on the dyno.
 

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